U.S. patent application number 15/004158 was filed with the patent office on 2016-06-09 for packaging machine and method.
The applicant listed for this patent is ULMA PACKAGING TECHNOLOGICAL CENTER. S.COOP. Invention is credited to Nerea ARBULU ORMAECHEA, Nicolas ARREGI ARAMBARRI, Eneko IZQUIERDO ERENO.
Application Number | 20160159507 15/004158 |
Document ID | / |
Family ID | 51212842 |
Filed Date | 2016-06-09 |
United States Patent
Application |
20160159507 |
Kind Code |
A1 |
IZQUIERDO ERENO; Eneko ; et
al. |
June 9, 2016 |
Packaging Machine and Method
Abstract
A modified atmosphere, skin or vacuum packaging machine
comprising first feed means adapted for feeding a first film to the
machine, second feed means adapted for feeding a second film to the
machine, and a sealing station where the vacuum is formed and/or
the modified atmosphere is introduced, and the second film is
sealed to the first film to obtain a package. The machine comprises
displacement means configured for moving at least the first film a
driving distance from an initial position, holding down and driving
at least the first film in the driving direction to an end
position, said displacement means being configured for subsequently
returning to the initial position when the machine is in operating
mode.
Inventors: |
IZQUIERDO ERENO; Eneko;
(Onati, ES) ; ARREGI ARAMBARRI; Nicolas; (Onati,
ES) ; ARBULU ORMAECHEA; Nerea; (Onati, ES) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ULMA PACKAGING TECHNOLOGICAL CENTER. S.COOP |
Onati |
|
ES |
|
|
Family ID: |
51212842 |
Appl. No.: |
15/004158 |
Filed: |
January 22, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2014/065588 |
Jul 21, 2014 |
|
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15004158 |
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Current U.S.
Class: |
53/511 ; 53/553;
53/561 |
Current CPC
Class: |
B65B 9/045 20130101;
B65B 11/52 20130101; B65B 9/04 20130101; B65B 31/046 20130101; B65B
47/06 20130101; B65B 2220/22 20130101; B65B 47/04 20130101; B65B
57/04 20130101; B65B 31/021 20130101; B65B 61/065 20130101 |
International
Class: |
B65B 31/04 20060101
B65B031/04; B65B 47/04 20060101 B65B047/04; B65B 61/06 20060101
B65B061/06; B65B 9/04 20060101 B65B009/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 24, 2013 |
ES |
P201331133 |
Claims
1. A packaging machine comprising: a first film feed assembly
configured to feed a first film to the packaging machine, a second
film feed assembly configured to feed a second film to the
packaging machine, a filling station located downstream the first
film assembly where a product to be packaged is placed onto the
first film, a sealing station located downstream the filling
station that is configured to receive the first film containing the
plurality of products with the second film lying over the plurality
of products, the sealing station configured to seal the second film
to the first film to obtain sealed packages, a displacement
assembly located downstream of the sealing station, the
displacement assembly including a moveable support moveable
longitudinally between a first position and a second position and
configured to engage the sealed first and second films and move the
sealed first and second films downstream away from the sealing
station from an initial position to an end position, the initial
position and the end position respectively corresponding to the
first and second positions of the moveable support, the moveable
support of the displacement assembly being configured to disengage
the sealed first and second films and return to the first position
upon the sealed first and second films having been placed in the
end position; and a cutting station to separate the sealed packages
into individual packages.
2. The packaging machine according to claim 1, wherein the
packaging machine is configured to operate intermittently between
an operating mode and a displacement mode, the packaging machine
being in the operating mode when the sealing station operates to
seal the second film to the first film to obtain the sealed package
and to form a-vacuum and/or introduce a modified atmosphere between
the first and second films, the moveable support of the
displacement assembly configured to engage the first film and the
second film in the areas not filled with product to move the films
downstream in a direction away from the sealing station from the
initial position to the end position when the packaging machine is
in the displacement mode, the moveable support of the displacement
assembly being configured to disengage the sealed first and second
films and return to the initial position when the packaging machine
is in the operating mode.
3. The packaging machine according to claim 2, wherein the
displacement assembly further comprises a fixed support that is
located downstream and stationary in relation to the moveable
support of the displacement assembly and spaced a first distance
apart from said moveable support, the fixed support comprising a
hold-down plate that is moveable between a first vertical position
and a second vertical position, in the first vertical position the
hold-down plate is configured to engage the areas not filled with
product of the first film and the second film to hold the films in
the end position, in the second vertical position the hold-down
plate is configured not to engage the sealed first and second
films, when the packaging machine is in the operating mode the
hold-down plate is configured to assume the first vertical
position, when the packaging machine is in the displacement mode
the hold-down plate is configured to assume the second vertical
position.
4. The packaging machine according to claim 3, wherein the moveable
support of the displacement assembly comprises a hold-down plate
that is moveable between a first vertical position and a second
vertical position, in the first vertical position the hold-down
plate is configured to engage the sealed first and second films to
hold and pull together the sealed first and second films from the
initial position to the end position as the moveable support moves
from the first position to the second position, in the second
vertical position the hold-down plate is configured not to engage
the sealed first and second films, when the packaging machine is in
the operating mode the hold-down plate is configured to assume the
second vertical position, when the packaging machine is in the
displacement mode the hold-down plate is configured to assume the
first vertical position.
5. The packaging machine according to claim 4, wherein the moveable
support of the displacement assembly comprises a support surface
located below the hold-down plate of he moveable support, the
support surface being configured to support the areas not filled
with product of the first film, and wherein the support surface
moves in unison with the movement of the moveable support.
6. The packaging machine according to claim 4, and wherein the
fixed support of the displacement assembly comprises a support
surface located below the hold-down plate of the fixed support, the
support surface being configured to support the areas not filled
with product of the first film.
7. The packaging machine according to claim 2, further comprising a
punch configured to produce one or more holes in the first film in
the areas designated not to be filled with product, the punch being
located between the first film feed assembly and the sealing
station.
8. The packaging machine according to claim 7, wherein the geometry
of the one or more holes is such that rounded corners are formed on
the border of the individual packages produced in the cutting
station.
9. A packaging machine comprising: a first film feed assembly
configured to feed a first film to the packaging machine, a second
film feed assembly configured to feed a second film to the
packaging machine, a thermoforming station located downstream the
first film assembly that is configured to act on the first film to
produce a plurality of containers that are separated by a
non-formed area of the first film, a sealing station located
downstream the thermoforming station that is configured to receive
the plurality of containers with the second film lying over the
plurality of containers, the sealing station configured to seal the
second film to the first film to obtain sealed packages, a first
displacement assembly including a moveable support moveable
longitudinally between a first position and a second position and
configured to engage at least a portion of the non-formed area of
the first film to move the plurality of containers downstream in a
direction away from the thermoforming station from a first initial
position to a first end position, the first initial position and
the first end position respectively corresponding to the first and
second positions of the moveable support, the moveable support
being configured to disengage the first film and return to the
first position upon the plurality of containers having been placed
in the first end position, the first displacement assembly being
located between the thermoforming station and the sealing station,
a second displacement assembly located downstream of the sealing
station, the second displacement assembly including a moveable
support moveable longitudinally between a first position and a
second position and configured to engage the sealed first and
second films and move the sealed first and second films downstream
away from the sealing station from a second initial position to a
second end position, the second initial position and the second end
position respectively corresponding to the first and second
positions of the moveable support, the moveable support of the
second displacement assembly being configured to disengage the
sealed first and second films and return to the first position upon
the sealed first and second films having been placed in the second
end position; and a cutting station to separate the sealed packages
into individual packages.
10. The packaging machine according to claim 9, wherein the
packaging machine is configured to operate intermittently between
an operating mode and a displacement mode, the packaging machine
being in the operating mode when the sealing station operates to
seal the second film to the first film to obtain the sealed
package, the moveable support of the first displacement assembly
configured to engage the non-formed area of the first film to move
the plurality of containers downstream in a direction away from the
thermoforming station from the first initial position to the first
end position when the packaging machine is in the displacement
mode, the moveable support of the first displacement assembly being
configured to disengage the first film and return to the first
position when the packaging machine is in the operating mode, the
moveable support of the second displacement assembly being
configured to engage the sealed first and second films to move the
sealed first and second films downstream in a direction away from
the sealing station from the second initial position to the second
end position when the packaging machine is in the displacement
mode, the moveable support of the second displacement assembly
being configured to disengage the sealed first and second films and
return to the first position when the packaging machine is in the
operating mode.
11. The packaging machine according to claim 10, wherein the first
displacement assembly further comprises a fixed support that is
located downstream and stationary in relation to the moveable
support of the first displacement assembly and spaced a first
distance apart from said moveable support, the fixed support
comprising a hold-down plate that is moveable between a first
vertical position and a second vertical position, in the first
vertical position the hold-down plate is configured to engage the
non-formed area of the first film to hold the plurality of
containers in the first end position, in the second vertical
position the hold-down plate is configured not to engage the first
film, when the packaging machine is in the operating mode the
hold-down plate is configured to assume the first vertical
position, when the packaging machine is in the displacement mode
the hold-down plate is configured to assume the second vertical
position, and wherein the second displacement assembly further
comprises a fixed support that is located downstream and stationary
in relation to the moveable support of the second displacement
assembly and spaced a first distance apart from said moveable
support, the fixed support comprising a hold-down plate that is
moveable between a first vertical position and a second vertical
position, in the first vertical position said hold-down plate is
configured to engage the sealed first and second films to hold the
sealed first and second films in the second end position, in the
second vertical position said hold-down plate is configured not to
engage the sealed first and second films, when the packaging
machine is in the operating mode said hold-down plate is configured
to assume the first vertical position, when the packaging machine
is in the displacement mode said hold-down plate is configured to
assume the second vertical position.
12. The packaging machine according to claim 11, further comprising
a punch configured to produce one or more holes in the non-formed
area of the first film, the punch being located between the first
film feed assembly and the sealing station.
13. The packaging machine according to claim 9, wherein the sealing
station includes a top mold and a bottom mold that when pressed one
against the other causes a sealing of the second film with the
non-formed areas of the first film, when the plurality of
containers are positioned in the sealing station the top mold is
configured to be situated above the plurality of containers and the
bottom mold is configured to be situated below the plurality of
containers.
14. The packaging machine according to claim 13, wherein the top
mold is configured to apply a vacuum above the second film to move
at least a portion of the second film away from the first film.
15. The packaging machine according to claim 14, wherein the bottom
mold is configured to apply a vacuum below the first film to
introduce a vacuum between the first and the second film through
the one or more holes when the plurality of containers are located
in the sealing station.
16. The packaging machine according to claim 15, wherein the bottom
mold comprises one or more nozzles that are configured to introduce
a modified atmosphere into the plurality of containers through the
one or more holes when the plurality of containers are located in
the sealing station.
17. The packaging machine according to claim 16 wherein the one or
more nozzles are moveable into and out of the one or more holes in
order to introduce a modified atmosphere into the plurality of
containers.
18. The packaging machine according to claim 14, wherein the bottom
mold is configured to introduce air between the first and the
second film through the one or more holes when the plurality of
products are located in the sealing station.
19. The packaging machine according to claim 14, wherein top mold
is configured to heat the portion of the second film moved away
from the first film.
20. The packaging machine according to claim 19, wherein the bottom
mold is configured to apply a vacuum below the first film to
introduce a vacuum between the first and the second film through
the one or more holes when the plurality of products are located in
the sealing station.
20. The packaging machine according to claim 19, wherein the top
mold is configured to apply a positive pressure above the second
film to cause the second film to move against the first film and to
seal in all the area around the product.
21. The packaging machine according to claim 20, further comprising
a pre-heating station that is configured to heat the second film
prior to the second film entering the sealing station.
22. The packaging machine according to claim 21, further comprising
a pre-sealing station located between the filling station and the
sealing station that is configured to induce a sealing of the first
and second films at discrete points so that gaps exists between the
discrete points.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application relates to and claims the benefit and
priority to International Application NO. PCT/EP2014/065588, filed
Jul. 21, 2014, which claims the benefit and priority to Spanish
Patent Application No. P201331133, filed Jul. 24, 2013.
TECHNICAL FIELD
[0002] The present invention relates to a method and a machine,
particularly a forming machine adapted for packaging products in a
modified atmosphere (also known as MAP packaging), vacuum packaging
products in a type of skin (also known as skin packaging) or vacuum
packaging products.
BACKGROUND
[0003] Vacuum or modified atmosphere packaging methods and
packaging machines are known.
[0004] Known packaging machines comprise first film feed means, a
thermoforming station where containers are made in the first film
inside which the product to be packaged will be introduced in a
later step, second film feed means, and a sealing station that is
supplied with both films and where the vacuum is formed or the gas
is introduced in the container containing the product to be
packaged. Subsequently in the sealing station, the second film is
sealed to the first film such that the package is obtained. In a
later step, cutting means comprised in the machine cuts the films
longitudinally and transversely, separating the packages that have
been formed.
[0005] Generally, as described in US2005/0173289A1, a packaging
machine of this type comprises chains guiding the movement of the
first film, said first film being fixed to said chains laterally,
such that it remains taut.
SUMMARY OF THE DISCLOSURE
[0006] The modified atmosphere or vacuum packaging machine
comprises a first film feed assembly/first feed means adapted for
feeding a first film to the machine, a second film feed
assembly/second feed means adapted for feeding a second film to the
machine, a sealing station where the vacuum is formed and/or the
modified atmosphere is introduced between both films and the second
film is sealed to the first film to obtain a package, and a
displacement assembly/displacement means adapted for moving the
first film in a driving direction.
[0007] The displacement assembly/displacement means is configured
for moving at least the first film a driving distance from an
initial position, holding down and driving at least the first film
in the driving direction to an end position, said displacement
assembly being configured for subsequently returning to the initial
position when the machine is in operating mode.
[0008] In addition, the modified atmosphere, skin or vacuum
packaging method comprises the following steps: [0009] feeding a
first film to the machine through first feed means, [0010]
positioning a second film on the first film after placing the
product to be packaged on the first film, [0011] forming a vacuum
and/or introducing the modified atmosphere between both films,
[0012] The displacement assembly holds down and drives the first
film a driving distance from an initial position to an end position
through the preceding steps when the machine is in displacement
mode, subsequently returning to the initial position when the
machine is in the operating mode.
[0013] A packaging machine and method that can reduce film waste
produced during the packaging process to a minimum are obtained.
Both the method and the machine are more efficient and at the same
time cleaner than any known in the state of the art because they
produce virtually no discarded film, using almost all the film. A
packaging machine and a packaging method that have less of an
impact on the environment are obtained. Furthermore, it allows
filling many type of skin package, including those packages
containing a product that projects above said package.
[0014] These and other advantages and features will become evident
in view of the drawings and the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 shows a side view of a skin packaging machine
according to one embodiment.
[0016] FIG. 2 shows a perspective view of the packaging machine
shown in FIG. 1.
[0017] FIG. 3 shows a detailed view of the machine shown in FIG. 1,
in which a forming station and displacement means of the machine
are shown in detail.
[0018] FIG. 4 shows a detailed view of the machine shown in FIG. 1,
in which a pre-sealing station, a sealing station, cutting means
and displacement means of the machine are shown in detail.
[0019] FIG. 5 shows a top view of a first film once it has gone
through the thermoforming step and the punching step.
DETAILED DESCRIPTION
[0020] The packaging machine 1 according to the invention can be a
modified atmosphere packaging machine, also known as a MAP
packaging machine, which wraps the product to be packaged in a
mixture of gases in the package, such that said mixture meets the
specific ventilation needs of the packaged product, or it can be a
vacuum packaging machine, or a skin packaging machine, being able
to package both products whose height is less than the height of a
tray where the product is placed and products projecting above the
tray.
[0021] FIG. 1 schematically shows a skin packaging machine 1
according to one embodiment. The machine 1 comprises a first film
feed assembly/first feed means 2 adapted for feeding a first film
30 to the machine 1, a thermoforming station 4 where at least one
container 32 is made in the first film 30 inside which the product
to be packaged is introduced in a filling station, a second film
feed assembly/second feed means 3 adapted for feeding a second film
31 to the packaging machine 1, and a sealing station 7 where a
vacuum is formed and the second film 31 is sealed to the first film
30 to obtain a package 34. The vacuum allows adjusting the second
film 31 to the shape of the product placed in the formed area 32,
obtaining a skin-type package 34.
[0022] In addition, one embodiment of the skin packaging method
comprises the following steps: [0023] feeding the first film 30 to
the machine 1 through the first feed means 2, [0024] positioning
the second film 31 on the first film 30 after placing the product
to be packaged on the first film 30, [0025] forming the vacuum
between both films 30 and 31, [0026] sealing both films 30 and 31
to obtain the package 34, and [0027] separating the package 34.
[0028] When the machine 1 is in any of the preceding steps, it is
in the operating mode where the displacement means 20 and 40 act to
hold down the first film 30, retaining it in a fixed position by
use of a first set of hold-down plates as will be described in
detail below. When the machine is in displacement mode, the
displacement means 20 and 40 hold down the first film 30 by use of
a second set of hold-down plates while pulling the film 30 in the
driving direction a driving distance to an end position. At said
end position, the displacement means 20 and 40 immobilize the first
film 30 by use of the first set of hold-down plates while the
displacement means 20 and 40 return to the initial position.
[0029] According to one embodiment the feed means 2 comprises at
least one reel and unwinding means driving the first film 30 to the
thermoforming station 4. Said feed means 2 is known in the state of
the art so it will not be described below.
[0030] In addition, films 30 and 31 can be made of any type of
plastic known for MAP, vacuum or skin packaging applications.
[0031] In addition, according to one embodiment the thermoforming
station 4 comprises a male mold 5 and a female mold 6 adapted for
obtaining the geometric shape of the container 32 and heating means
not depicted in the drawings that heats the first film 30 in order
to carry out the thermoforming process. Other thermoforming
stations known in the state of the art, for example vacuum or
pressure thermoforming stations, can be used in other embodiments.
Containers 32, also known as trays, are formed in the first film 30
in the thermoforming station 4, and are then separated from one
another in areas referred to as non-formed areas 33.
[0032] If a single package 34 is going to be made, a single
container 32 will be formed in the first film 30, the non-formed
area 33 being the area on the perimeter of said container 32. Said
non-formed area 33 will make up the border 35 of the package 34
that is obtained. If a plurality of packages 34 is going to be
made, a plurality of containers 32 surrounded by non-formed areas
33 which will respectively form the border 35 of the corresponding
package 34 that is obtained will be formed in the thermoforming
station 4, reducing waste to a minimum in the first film 30.
[0033] In other non-depicted embodiments, the machine 1 may not
include a thermoforming station. In said cases, the product to be
packaged rests directly on the first film 30 or on a base that is
arranged on said first film 30 and on which the product is
supported.
[0034] As noted above, the machine 1 comprises displacement means
20 and 40 adapted for moving the first film 30 in the driving
direction.
[0035] Once the containers 32 are formed in the first film 30, said
first film 30 is moved by a first displacement assembly/first
displacement means 20 in the driving direction to a filling station
where the product to be packaged is placed on each container 32.
Said filling can be done either manually or automatically.
[0036] The first film 30, now formed as one or more containers 32,
is then moved by the second displacement means 40 to the sealing
station 7. At the same time, the second feed means 3 feeds the
second film 31 to said sealing station 7. Said sealing station 7
comprises a top mold 8, a bottom mold 9, heating means (not
depicted in the drawings) adapted for heating the top mold 8,
vacuum means (not depicted in the drawings) adapted for creating
the vacuum, and aeration means (no shown in the drawings) acting on
the top mold 8. When the second film 31 enters the sealing station
7, a vacuum is applied to the top mold 8 such that said second film
31 is deformed towards the top mold 8 (which is previously heated),
where said second film 31 is heated. At the same time, the first
film 30 is positioned on the bottom mold 9. A vacuum is applied
from the bottom mold 9, and then it is aerated from the top mold 8
such that the second film 31 is sealed to the first film 30 along
the entire contact surface, deforming said second film 31 due to
the effect of heating and adapting to the shape of the product
placed in the container 32, such that a plurality of packages 34
are formed, that is, as many packages 34 are formed as containers
32 were made in the thermoforming station 4, such containers 34
being fixed to one another through the non-formed areas 33
corresponding with the border 35 of the package 34. In a later
step, said packages 34 are separated from one another through the
borders 35.
[0037] If the product to be packaged projects above the non-formed
area 33 once the product is introduced, the second film 31 must be
heated before being introduced in the sealing station 7 in order to
adapt to the shape of the product to be packaged when it is
positioned on the first film 30. To that end, the machine 1 further
comprises a heating station where the second film 31 is heated
before being introduced in the sealing station 7 to make the second
film 31 more ductile. The machine 1 comprises auxiliary
displacement means 53 keeping the second film 31 clamped as it
moves through the heating station, preventing it from shrinking
while it is heated. Said auxiliary displacement means 53 releases
the second film 31 when it comes out of the heating station. Said
release occurs close to the area where both films 30 and 31 come
into contact with one another for the first time.
[0038] The machine 1 may further comprise pre-sealing means 52
arranged before the sealing station 7. Particularly, said
pre-sealing means 52 is arranged where first contact between both
films 30 and 31 occurs, i.e., where the second film 31 leaves the
auxiliary displacement means 53. Said pre-sealing means 52 is
adapted for sealing the second film 31 to the first film 30
longitudinally at discrete points. Sealing is preferably performed
by heat sealing, although in other embodiments sealing may be
performed by high-frequency welding or by other known sealing
methods. Therefore, by keeping the films 30 and 31 aligned with one
another by means of sealing at certain points from the moment both
films 30 and 31 enter the sealing station, the second film 31
adapts to the product to be packaged better when products whose
height exceeds the height of the corresponding container 32 are
packaged. Once in the sealing station 7, the vacuum and sealing
process is similar to that previously described.
[0039] In a one embodiment, the auxiliary displacement means 53
comprises a belt 54, guide rollers 55 moving the belt 54 and a
counter-belt 56 holding the second film 31, clamping it against the
belt 54. The belt 54 moves in synchronization with the displacement
means 20 and 40 of the machine 1. Furthermore, the pre-sealing
means 52 comprises a first gear wheel 57 coupled to a guide roller
55 of the auxiliary displacement means 53 and a second wheel 58
arranged below the first film 30. The second wheel 58 can be a gear
wheel or a smooth welding roller. The first wheel 57 is arranged in
the guide roller 55 arranged closest to the first film 30. The
teeth of the first wheel 57 go through the belt 54 which has holes
in it, being supported on the second wheel 58, thereby pressing the
second film 31 against the first film 30. Said second wheel 58 is
heated, both films 30 and 31 being welded to one another at
discrete points as both wheels 57 and 58 rotate, moving both films
30 and 31 towards the sealing station 7.
[0040] In other embodiments, the auxiliary displacement means can
comprise clamps which fix the taut second film 31 to the chain and
gear wheels adapted for closing the clamps before entering the
heating station and for opening said clamps after exiting the
heating station. The clamps can be covered with a ductile material
which holds the second film 31 without leaving marks.
[0041] As noted above, the pre-sealing means may comprise a gear
wheel arranged below the first film 30 such that the teeth of the
gear wheel of the auxiliary displacement means arranged closest to
the first film 30 are supported on the respective teeth of the gear
wheel arranged below the first film 30, thereby pressing the second
film 31 against the first film 30, both films 30 and 31 being
welded to one another at discrete points as both wheels rotate,
moving both films 30 and 31 towards the sealing station 7.
[0042] In other embodiments, gear wheels are not necessary, the
pre-sealing being performed as both films 30 and 31 move forward
using any known conventional welding means.
[0043] In addition, between the thermoforming station 4 and the
sealing station 7, the packaging machine 1 comprises a longitudinal
support 10 for the first film 30.
[0044] In one embodiment, the longitudinal support 10 comprise at
least one longitudinal guide 11 on which the first film 30 is
supported. The first film 30 is supported on said longitudinal
guide 11 on the non-formed area 33 comprised between two
consecutive containers 32. For every N containers 32 formed in the
first film 30 transverse to the forward movement, N+1 non-formed
areas 33 arranged between two consecutive containers 32 are formed,
therefore N+1 longitudinal guides being arranged fixed to a frame
50 of the machine 1 on which the first film 30 is supported.
[0045] In other embodiments, particularly when thermoforming a
single package 34, the longitudinal support 10 comprises a bearing
surface under the first film 30 on which a bottom of the container
32 is supported. The bearing surface can be a planar surface, for
example a table, over which the first film 30 slides with the
product placed in the containers 32. In other embodiments, the
longitudinal support 10 comprises a set of transversely arranged
rollers (not depicted in the drawings) forming the bearing surface
over which the first film 30 slides with products with minimum
friction. The set of rollers is generally necessary when the
products to be packaged are heavy in order to prevent high friction
during movement. In addition, for said longitudinal support 10 to
adapt to any depth of the containers 32, the height of the bearing
surfaces can be adjusted.
[0046] In other embodiments, the longitudinal support 10 can
comprise both the longitudinal guides and the bearing surfaces.
[0047] In other embodiments, the longitudinal support 10 can
comprise a retractable conveyor belt adapted for moving together
with the first film 30 with the products introduced therein into
the sealing station 7, the conveyor belt being able to go back out
of the sealing station 7 once the first film 30 with the products
therein is placed on it.
[0048] As noted above, the displacement assemblies/displacement
means 20 and 40 are configured for retaining the first film 30 in a
specific position when the machine 1 is in the operating mode. The
displacement means 20 and 40 are also configured to drive the first
film 30 in the driving direction when the machine 1 is in forward
movement mode/displacement mode. Said displacement means 20 and 40
are configured for holding down and moving the first film 30 in
displacement mode. In addition, the machine 1 is considered to be
in the operating mode when it is performing a thermoforming,
vacuum, sealing or cutting operation on the package.
[0049] In the embodiment shown in the drawings, the first
displacement means 20 is arranged between the thermoforming station
4 and the sealing station 7, particularly between the thermoforming
station 4 and the filling station, and the second displacement
means 40 is arranged after the sealing station 7.
[0050] In the embodiment shown in the drawings, the first
displacement means 20 comprises a first fixed support 22 arranged
stationary with respect to the frame 50 of the machine 1 and at a
location between the thermoforming station 4 and the sealing
station 7. The second displacement means 40 comprises a second
fixed support 29 arranged stationary with respect to the frame 50
of the machine 1 and at a location after the sealing station 7. The
first displacement means 20 also includes a first movable support
21 movable in the driving direction with respect to the first fixed
support 22. The second displacement means 40 also includes a second
movable support 28 movable in the driving direction with respect to
the second fixed support 29.
[0051] According to some embodiments, each of the fixed supports 22
and 29 has a substantially bridge-shaped geometry. Each of the
fixed supports 22 and 29 respectively comprises a support 24 and 27
on which the first film 30 may be arranged. Fixed support 22
includes one or more hold-down plates 23 configured for pressing
the first film 30 against the support 24. Likewise, fixed support
29 includes one or more hold-down plates 26 configured for pressing
the first film 30 against the support and 27. The hold-down plates
23 and 26 are configured to press the first film against the
respective supports 24 and 27 to keep the first film 30 retained in
the specific position when the machine 1 is in operating mode. Each
hold-down plate 23 and 26 is arranged facing the corresponding
support 24 and 27, the first film 30 being arranged between
both.
[0052] According to some embodiments each of the movable support 21
and 28 has a substantially bridge-shaped geometry. Each of the
movable supports 21 and 28 respectively comprises supports 44 and
47 on which the first film 30 may be arranged. Moveable support 21
includes one or more hold-down plates 43 configured for pressing
the first film 30 against the support 44. Moveable support 28
includes one or more hold-down plates 46 configured for pressing
the first film 30 against the support 47. The hold-down plates 43
and 46 are respectively arranged facing the corresponding support
44 and 47 with the first film 30 being arranged between both.
According to one embodiment, each of the movable supports 21 and 28
comprises a vertical actuation drive (not depicted) acting on the
corresponding hold-down plate 43 and 46, moving said hold-down
plate 43 and 46 vertically with respect to the first film 30. Said
drive may be a pneumatic cylinder.
[0053] The displacement means 20 and 40 respectively comprise
guides 60 and 62 and a longitudinal actuation drive acting on the
corresponding movable supports 21 and 28, moving them in the
driving direction through the guides. Both the guides and the drive
are arranged below the first film 30. The drive can be pneumatic,
hydraulic or any other type known in the state of the art. The
displacement means 20 and 40 act in a synchronized manner, moving
the first film 30 forward intermittently. When the machine 1
operates in the operating mode, the movable supports 21 and 28 are
arranged in the position furthest away from the fixed supports 22
and 29, the vertical drives corresponding to the hold-down plates
23 and 26 of the fixed supports 22 and 29 are activated, pressing
the hold-down plates 23 and 26 against the first film 30, while the
hold-down plates 43 and 46 of the movable supports 21 and 28 are
not active and are therefore separated from the first film 30. The
package thermoforming, sealing, vacuum and cutting operation will
be performed in that position. In order to move the first film 30,
once the operating mode ends, the vertical drives corresponding to
the hold-down plates 43 and 46 of the movable supports 21 and 28
are activated, applying pressure on the first film 30 against the
corresponding supports 44 and 47; the vertical drives corresponding
to the hold-down plates 23 and 26 of the fixed supports 22 and 29
are deactivated said hold-down plates 23 and 26 being separated
from the first film 30; and the longitudinal drives are activated,
moving the movable supports 21 and 28 in the driving direction and
therefore moving the first film 30 to the next position where the
first film 30 is retained again. When the movable supports 21 and
28 are arranged in the end position, the vertical actuator
corresponding to the hold-down plates 43 and 46 of the movable
bearings 21 and 28 are deactivated, releasing the first film 30,
while the vertical actuator corresponding to the hold-down plates
23 and 26 of the fixed supports 22 and 29 is activated, pressing
said hold-down plates 23 and 26 against the corresponding supports,
fixing the first film 30 in the end position. The movable supports
21 and 28 are moved by the corresponding longitudinal actuator to
the initial position, i.e., starting position, repeating the same
forward movement cycle.
[0054] The hold-down plates 23, 26, 43 and 46 are supported on the
non-formed areas 33 of the first film 30, not on the containers 32
where the product to be packaged will later be placed. In the
embodiment shown in the drawings, the hold-down plates 23, 26, 43
and 46 have an elongated, flat bar-type geometry. Said hold-down
plates 23, 26, 43 and 46 are longitudinally aligned, acting on the
non-formed areas 33 comprised on the edges of the first film
30.
[0055] In other embodiments, the displacement means 20 may comprise
a hold-down plate 23, 26, 43 and 46 arranged longitudinally acting
on the non-formed areas 33. So for every N containers 32
transversely formed in the first film 30, N+1 non-formed areas 33
are formed, N+1 hold-down plates 23, 26, 43 and 46 therefore being
arranged.
[0056] Furthermore, according to some embodiments, each of the
hold-down plates 23, 26, 43 and 46 has a length substantially equal
to the pitch of the machine 1, the pitch of the machine being
understood as the distance that the first film 30 moves forward
when the machine 1 is in the displacement mode, and a width
substantially equal to the width of the corresponding non-formed
area 33. If the non-formed area 33 corresponds to a non-formed area
33 between two consecutive containers 32, the width of the
hold-down plate will be substantially twice that of the previous
one.
[0057] In other embodiments, the hold-down plates 23, 26, 43 and 46
may be arranged transverse to the driving direction.
[0058] In other embodiments, the displacement means 20 and 40 can
respectively be included in the thermoforming station and in the
sealing station, such that the top and bottom molds of each station
perform movable support functions, the hold-down plates are the top
molds, while the bottom molds perform the support function.
[0059] In addition, the machine 1 may comprise punching means 15
adapted for punching the first film 30 in a non-formed area 33. The
punching operation is performed before said first film 30 reaches
the sealing station 7, particularly before the step of introducing
the product in the container 32. In the embodiment shown in the
drawings, the punching means 15 is comprised in the displacement
means 20. According to such an embodiment the punching means 15 may
comprise at least one punch coupled to the first fixed support 22
that is arranged stationary in relation to the frame 50 of the
machine 1 between the thermoforming station 5 and the sealing
station 7.
[0060] The punching means 15 is configured to produce at least one
hole 17 and/or a notch 18 in the non-formed area 33. In one
embodiment, the punching means 15 produces a notch 18 or a hole 17
at the intersection of the non-formed areas 33 when the machine 1
is in the operating mode. The notches 18 are made on the edges of
the first film 30 while the holes 17 are made at the intersections
of the inner non-formed areas 33. The geometry of the holes 17
and/or notches 18 is such that it forms rounded corners 35b on the
border 35 of the package 34. In one embodiment, as shown in the
drawings, each hole 17 has a rosette-shaped geometry made at the
intersection of two non-formed areas 33 and each notch 18 has a
half rosette-shaped geometry.
[0061] In one embodiment, the holes 17 are used for performing
evacuation in the sealing station 7. The notches 18 further allow
correctly positioning the second movable support 28, particularly
the hold-down plates 46 of said second movable support 28, which
allows moving the first film 30 forward a predetermined distance,
such that it is positioned correctly inside the respective stations
of the machine 1. To that end, the machine 1 may further comprise
detection means (not depicted) configured for detecting the notches
18 and control means which position the displacement means 20 and
40 in the place indicated according to the detected values.
[0062] When thermoforming a single container 32, and therefore
intermittently forming a single package 34, the punching means 15
only produces notches 18. Therefore, given that the non-formed
areas 33 are held down during vacuum formation and sealing by the
molds 8 and 9 of the sealing station 7, in order to form the
vacuum, the bottom mold 9 includes side openings through which the
vacuum is formed. Otherwise, the vacuum and sealing process is
equal to that previously described. At the same time, excess
pressure is applied from the top mold 8 such that the second film
31 is sealed to the first film 30 along the perimeter of the
non-formed areas 33, deforming due to the effect of heating and
adapting to the shape of the product.
[0063] In another embodiment the manufacturing method does not
comprise the step of making holes 17 with the punching means 15. In
this case, the second film 31 is sealed to the first film 30
longitudinally at discrete points by the pre-sealing means 52.
Subsequently, in the sealing station 7 a nozzle is introduced
through the openings formed between the sealed discrete points,
forming the vacuum through said nozzles. The nozzles are then
retracted. By providing aeration from the top mold and forming the
vacuum from the bottom mold, the second film 31 is sealed along the
entire contact surface of the first film 30 due to the
compatibility of said films 30 and 31 and the prior heating of the
second film 31 in the top mold 8.
[0064] In addition, the machine 1 comprises cutting means adapted
for longitudinally and/or transversely cutting the films 30, 31,
separating the formed packages 34 in the sealing station 7.
[0065] In the embodiment shown in the drawing, the cutting means
comprise longitudinal blades 16 coupled to the second fixed support
29 of the displacement means 40. Said longitudinal blades 16
longitudinally cut the films 30 and 31, going through the
corresponding holes 17. The cutting means further comprises
transverse blades coupled to the frame 50 of the machine 1, adapted
for transversely cutting the films 30 and 31, going through the
holes 17 and/or the notches 18 and separating the packages 34. In
other embodiments, the transverse blades and longitudinal blades
are arranged in the second fixed support 22 of the displacement
means 20.
[0066] Although the described embodiments relate to skin packaging
methods and machines, the previous description can be applied to a
vacuum or modified atmosphere packaging machine and method with the
exception of that corresponding to the sealing station. In a
modified atmosphere package manufacturing machine, the sealing
station comprises a top mold, a bottom mold, sealing means for
sealing the second film 31 to the first film 30, particularly
around the borders 35 of the package 34, evacuation means for
evacuating gases from the package 34 that may exist and filling
means introducing the desired gas or gases in the package 34. Such
sealing stations are known in the state of the art, so they will
not be described in detail. Once the first film 30 and the second
film 31 are introduced in the sealing station, evacuation is
performed and gases are injected through the filling means, through
the holes 17 made by the punching means 15, the second film 31
being sealed to the first film 30 along the non-formed areas 33. In
order to assure that the second film 31 does not block said holes
17 during the evacuation operation and while the gas or gases are
being introduced, the sealing station 7 comprises a tool or nozzle
introduced through the hole 17 to allow evacuating and introducing
gas.
[0067] If a single package 34 is manufactured, a leak-tight cavity
in which the films 30 and 31 are placed is formed, taking into
account that the molds do not close against the non-formed area 32,
the vacuum means cause the second film 31 to swell up, generating a
gap between both films 30 and 31 where nozzles through which gas is
injected are introduced. The nozzles are then retracted and both
films 30 and 31 are sealed to one another along the non-formed area
33.
[0068] In one embodiment of the manufacturing method in which the
punching means 15 only makes notches 18 on the edges of the first
film 30, the second film 31 is sealed to the first film 30
longitudinally at discrete points in the pre-sealing station 52.
Then in the sealing station, nozzles are introduced through the
openings formed between the sealed discrete points, performing
evacuation and filling through said nozzles. Said nozzles are then
retracted, both films 30 and 31 being sealed to one another. Then
in the cutting step, the corners 35b of the borders 35 of the
package 34 are rounded.
[0069] The previous description relating to a modified atmosphere
packaging machine can be applied to a vacuum packaging machine,
with the difference that the process of filling the package with
gas after forming the vacuum is not performed.
[0070] The machine 1 is adapted for making one or more packages
arranged in parallel and one or more series of packages in parallel
in each operating mode, such that the machine can be readily
adapted to different configurations of packages to be formed.
* * * * *